Inspection Procedure 12
INSPECTION PROCEDURE 12: Gear NoiseNOTE: Noise from the engine, mummer vibration, transmission, propeller shaft, wheel bearings, fires, body, etc., is easily mistaken as being caused by malfunction in the differential carrier components. Be extremely careful and affective when test driving, etc.
Test methods to confirm the source of the abnormal noise include: coasting, acceleration, constant speed driving, raising the rear wheels, etc. Use the method most appropriate to the circumstances.
DIAGNOSIS
STEP 1. Check that Hypoid gear oil MITSUBISHI Genuine Gear Oil Part No.8149630 EX or equivalent is being used.
Q: Is the Hypoid gear oil MITSUBISHI Genuine Gear Oil Part No.8149630 EX or equivalent being used?
YES: Go to Step 2.
NO: Replace the oil. Then go to Step 9.
STEP 2. Check the oil level.
Remove the filler plug and check the gear oil level.
Q: Is the gear oil level more than 8 mm (0.3 inch) below the bottom of the filler plug hole?
YES: Check the oil leakage from differential carrier, and repair if necessary. Then refill Hypoid gear oil MITSUBISHI Genuine Gear Oil Part No.8149630 EX or equivalent. Then go to Step 9.
NO: Go to Step 3.
STEP 3. Check the tooth contact (engagement) of the drive gear.
Q: Is the tooth contact (engagement) of the drive gear correct?
YES: Go to Step 4.
NO: Adjust or replace the part. Then go to Step 9.
STEP 4. Check the drive gear backlash.
Q: Is the drive gear backlash correct?
YES: Go to Step 5.
NO: Adjust the backlash. Then go to Step 9.
STEP 5. Check the drive pinion turning torque.
Q: Is the drive pinion turning torque correct?
YES: Go to Step 6.
NO: Adjust the turning torque. Then go to Step 9.
STEP 6. Check the drive gear and drive pinion for tooth damage or breakage.
Q: Are the drive gear and drive pinion for tooth damaged?
YES: Replace the part. Then go to Step 9.
NO: Go to Step 7.
STEP 7. Check the drive pinion bearing and side bearing for seizure, damage or breakage.
Q: Are the drive pinion bearing and side bearing damaged?
YES: Replace the part. Then go to Step 9.
NO: Go to Step 8.
STEP 8. Check the limited slip differential case assembly for damage.
Q: Is the limited slip differential case assembly damaged?
YES: Replace the part. Then go to Step 9.
NO: Go to Step 9.
STEP 9. Check symptoms.
Q: Is the gear noise eliminated?
YES: Diagnosis is complete.
NO: Start over at Step 1.